Development and regulation of calcium metabolism in healthy girls

被引:24
作者
Bronner, F [1 ]
Abrams, SA
机构
[1] Univ Connecticut, Ctr Hlth, Dept Biostruct & Funct, Farmington, CT 06030 USA
[2] Baylor Coll Med, Dept Pediat, USDA ARS, Childrens Nutr Res Ctr, Houston, TX 77030 USA
关键词
calcium absorption rate in healthy girls; bone calcium deposition rate; bone calcium removal rate; exchangeable bone calcium; age-dependent changes;
D O I
10.1093/jn/128.9.1474
中图分类号
R15 [营养卫生、食品卫生]; TS201 [基础科学];
学科分类号
100403 ;
摘要
The major components of calcium metabolism, as evaluated by a dual-tracer stable isotope method, were determined in 100 studies of 68 healthy girls, aged 5-18 y and analyzed from a developmental and regulatory viewpoint. Bone calcium deposition and removal rates were closely correlated with the size of the exchangeable bone calcium compartment. All three quantities, as well as intestinal calcium absorption, peaked at or near menarche. Both bone calcium deposition and removal rates were positively and linearly correlated with calcium absorption. However, in this correlation, because bone calcium deposition increased 70% faster than calcium absorption, most of the increase in the bone calcium compartment and its turnover must have occurred in response to something other than intestinal calcium input; presumably this occurred in response to developmental signals. Nevertheless, the constancy of the serum calcium in the face of a large intestinal calcium input and the modest way in which excretion overcame the calcium load in this population point to the importance of the exchangeable bone calcium compartment, in dynamic equilibrium with the bone mineral, as the site at which most of the load is taken up. In this population of girls, as in older women, this increase in the skeletal calcium balance resulted from a decrease in the bone calcium removal rate that was greater than the corresponding increase in the bone calcium deposition rate.
引用
收藏
页码:1474 / 1480
页数:7
相关论文
共 30 条